[A case of polymyalgia rheumatica where a complication of large-vessel vasculitis was diagnosed by FDG-PET].

The patient was a 74-year-old female presenting with abrupt onset of fever and proximal muscle pains. She had been diagnosed with polymyalgia rheumatica (PMR). On physical examination, there was no tenderness or dilatation of the temporal artery and ocular fundi were normal. 18F-FDG-PET revealed accumulation of FDG in the aorta as well as in the bilateral subclavian arteries, which strongly suggested inflammation of the large blood vessels. Magnetic resonance angiography disclosed stenosis of the bilateral subclavian arteries, which was consistent with angitis. This case was considered to have developed PMR at an old age with positive HLA DR4, and to have a complication large-vessel giant cell arteritis (LV-GCA). Administration of prednisolone at a dose of 20 mg/day promptly relieved the fever and the myalgia as well. It is difficult to diagnose GCA in PMR if no tenderness or dilatation of the temporal artery is present. FDG-PET is considered useful, not only for exploration of tumors, but also for evaluation of inflammation of large vessels.

Differences in the effects of Na+-H+ exchange inhibitors on cardiac function and apoptosis in guinea-pig ischemia-reperfused hearts.

The protective effects of the Na+-H+ exchange (NHE) inhibitors SM-198110 (2-[[(aminoiminomethyl) amino] carbonyl]-4-chloro-1H-indole-1-propanesulfonic acid monohydrate) and SM-197378 (N-(aminoiminomethyl)-1-methyl-7-(sulfooxy)-4-(trifluoromethyl)-1H-indole-2-carboxamide monohydrate) were investigated in perfused Langendorff guinea-pig hearts subjected to ischemia (40 min) and reperfusion (40 min). The recovery of left ventricular developed pressure (LVDP) from ischemia by reperfusion was 39.0% in the control, while in the hearts pretreated with SM-198110 or SM-197378 (10(-7) M), it was about 100%. The ATP level, monitored simultaneously by (31)P-nuclear magnetic resonance spectrometry, was already higher than the control value at the end of the ischemic period, and the elevation in Na+ or Ca2+ fluorometric signals induced during ischemia was suppressed. In post-treated hearts, the LVDP recovery rate was significantly higher with SM-198110 than with SM-197378. By in vitro electron paramagnetic resonance spectrometry, SM-197378 was found to directly quench the active oxygen radical, whereas SM-198110 had no effect. Numbers of apoptotic cardiomyocytes after ischemia (1 h) followed by reperfusion (5 h) were significantly lower in SM-197378-treated than in SM-198110-treated hearts, consistent with the level of activity of caspase-3. These results suggest that the antioxidant effects of NHE inhibitors have an important role in apoptosis during ischemia-reperfusion, but apoptosis is not a major manifestation of cardiac function during postischemic recovery, and that NHE-sensitive mechanisms of reperfusion injury promote both necrotic and apoptotic processes death.

Primary lymphoma of the heart: case report and literature review.

Primary cardiac lymphoma (PCL) is a rare and usually fatal neoplasma. A case of PCL in a 78-year-old man who complained of exertional dyspnea and peripheral edema is presented. Echocardiography revealed a mass in the right atrium and a diagnosis of low-grade B-cell lymphoma was obtained with the surgically resected tumor. The lesion appeared to have originated in the right atrium and involved the right ventricle. The patient died of bronchopneumonia 8 months after the initial consultation. The present case and 39 patients with PCL reported between 1995 and 2002 were reviewed. Forty patients showed various and non-specific symptoms such as dyspnea, edema, arrhythmia and pericardial effusion. Primary cardiac lymphoma occurred slightly more often in male patients (M : F = 23:17) and in the elderly in general (mean age, 67 years), with lesions found in the following locations, listed in order of frequency: right atrium, pericardium, right ventricle, left atrium, left ventricle, and other sites. Antemortem diagnosis was obtained in 37 of the 40 patients. Thirty-seven cases were of B-cell lineage and two cases were of T-cell lineage. Complete remission was obtained in only 15 of the 40 patients. Although PCL antemortem diagnoses have been made in the majority of recent cases, the prognosis still remains poor.

The G12 family of heterotrimeric G proteins and Rho GTPase mediate Sonic hedgehog signalling.

Sonic hedgehog (Shh) is a secreted morphogen crucial for cell fate decision, cellular proliferation, and patterning during vertebrate development. The intracellular Shh signalling is transduced by Smoothened (Smo), a seven-transmembrane spanning protein that belongs to the G-protein coupled receptor family. Among four families of Galpha subunits, Galphai has been thought to be responsible for transducing Shh signalling, while several lines of evidence indicated that other signalling pathways may be involved. We found that the G12 family of heterotrimeric G proteins and the small GTPase RhoA are involved in Shh/Smo-mediated cellular responses, including stimulation of target gene promoter and inhibition of neurite outgrowth of neuroblastoma cells. We also found that the G12/RhoA pathway is responsible for Smo-induced nuclear import of GLI3 which is thought to transduce Shh signals to nucleus. Furthermore, misexpression of a G12-specific GTPase-activating protein in rat neural tubes leads to pertubation of motor neurone and interneurone development, mimicking the effects of decreased Shh signalling. These results show that Shh signalling is mediated in part by activating G12 family coupled signalling pathways. The participation of RhoA, a pivotal molecular switch in many signal transduction pathways, may help explain how Shh can trigger a variety of cellular responses.

A role of activated Sonic hedgehog signaling for the cellular proliferation of oral squamous cell carcinoma cell line.

Sonic hedgehog (Shh) is a secreted morphogen crucial for appropriate cellular proliferation during mammalian development. The activated Shh signaling is known to predispose to human tumors such as medulloblastoma and basal cell carcinoma, while a role of Shh signaling in the other common tumors is still controversial. Here we showed the overexpression of Shh in five cell lines among 14 human oral squamous cell carcinoma (OSCC) cell lines. One of the Shh-expressing OSCC cell lines HSQ-89 showed the inhibition of G1/S transition and apoptotic cell death by treatment with Cyclopamine, a steroidal alkaloid that blocks the intracellular Shh signaling. Furthermore, we found that treatment with Y-27632, a specific inhibitor of Rho-associated kinase, mimicked the effect of Cyclopamine on the cell cycle progression of HSQ-89. Our study revealed the involvement of activated Shh signaling in the cellular proliferation of OSCC cells, indicating Shh signaling might be a good therapeutic target for OSCC.

Diversity of restitution after deoxycholic acid-induced small intestinal mucosal injury in the rat.

Repair of superficial damage to gastrointestinal mucosa occurs by a process called restitution, with epithelial integrity and continuity reestablished before cell proliferation occurs. The aim of the present study was to investigate the diversity of restitution in rat jejunum exposed to different concentrations of deoxycholic acid (DOC; 1.5-100 mmol/liter). Following a 30-min exposure, the intestine was allowed to recover for 15-330 minutes. DOC caused dose-dependent tissue destruction. Exfoliating epithelial cells were already observed after 5 min of exposure (1.5 mmol/liter), with simple sloughing off and resealing of the tips. Moderately affected epithelium (20 mmol/liter) demonstrated denudation of villous tips and then became covered with goblet cells. Severely affected epithelium (100 mmol/liter) also appeared to be replaced with goblet cells. These data suggest that the reversibility of mucosal damage induced by DOC is due to a variety of processes, which depend on the severity of the mucosal insult.

Rat small intestinal goblet cell kinetics in the process of restitution of surface epithelium subjected to ischemia-reperfusion injury.

Repair of superficial damage to gastrointestinal mucosa occurs by a process called restitution. Goblet cells reside throughout the length of the intestine and are responsible for the production of mucus. However, a kinetic analysis of goblet cell dynamics of small intestine in restitution has hitherto not been reported. The aim of the present study was to investigate the role of goblet cells in the process of restitution of rat small intestine subjected to ischemia and ischemia-reperfusion injury, and therefore intestinal epithelium from rats subjected to both ischemia and ischemia-reperfusion was studied. Detachment of enterocytes was observed after 5-min of reperfusion. After 20-30 minutes of reperfusion, the denuded villous tips were covered with goblet cells. Within 75 min of reperfusion the epithelium restitution was complete. On the other hand, restitution was not observed in ischemia group. These data suggest that goblet cells may play an important role in restitution after ischemia-reperfusion injury.